Sufficiency of a sufficient statistic for equivariant estimation

Suppose an estimation problem is invariant under a group of transformations and one is interested in finding an optimal equivariant estimator. The usual proactice is to confine attention to non-randomized equivariant estimators based on a minimal sufficient statistic. A justification of this restriction to a smaller clas of estimators is given in this paper under certain conditions.     

The effects of correlation among observations on the consistency property of sample variance

It is well known that even when the sample observations are correlated and not normal the sample variance, S² converges in probability to E(S²). But the required sample size for S² to be a consistent estimator of E(S²) is an open question. Some light is shed on this question in this paper. In particular the relation between the rate of convergence and the correlation property of the observations is explored. It is shown that the retardation to the rate of convergence is not appreciable if the correlation is moderate but it can be severe for extreme correlations.     

THE EFFECTS OF CORRELATION AMONG OBSERVATIONS ON THE ACCURACY OF APPROXIMATING THE DISTRIBUTION OF SAMPLE MEAN BY ITS ASYMPTOTIC DISTRIBUTION1

In this paper, we investigate the effects of correlation among observations on the accuracy of approximating the distribution of sample mean by its asymptotic distribution. The accuracy is investigated by the Berry-Esseen bound (BEB), which gives an upper bound on the error of approximation of the distribution function of the sample mean from its asymptotic distribution for independent observations. For a given sample size (n₀) the BEB is obtained when the observations are independent. Let this be BEB. We then find the sample size (n_*) required to have BEB below BEB₀, when the observations are dependent. Comparison of n_* with n₀ reveals the effects of correlation among observations on the accuracy of the asymptotic distribution as an approximation. It is shown that the effects of correlation among observations are not appreciable if the correlation is moderate to small but it can be severe for extreme correlations.     

外包趋势不可逆 奥巴马的政治限制影响甚微

自从奥巴马接任美国总统以来，严重依赖美国的印度外包产业一度感到胆战心惊：首先，奥巴马大幅减少了允许外国工人在美国本土就业的H-1b工作签证；接着奥巴马又在2月24日的国会讲话中宣布“终止美国公司外包业务的减税优惠”。     

Subsidiary power,cultural intelligence and interpersonal knowledge transfer between subsidiaries within the multinational enterprise

We propose that individual-level knowledge transfer between subsidiaries within a multinational enterprise depends on the perceived relative power of the subsidiary and the cultural intelligence of individuals. Using a sample of 333 research and development (R&D) subsidiary employees of foreign Multinational Enterprises (MNEs) in India, we find that the perceived subsidiary power has a direct positive significant effect on knowledge sharing, and an indirect significant effect, through organizational identification, on knowledge seeking. Further, cultural intelligence moderates the effect of organizational identification on knowledge seeking, and the indirect effect of the perceived subsidiary power on it. The findings highlight the role of organizational identification and cultural intelligence in explaining the impact of the perceived subsidiary power on interpersonal knowledge transfer within the MNE.     

The intersection of social protection and mobilities: a move towards a ‘Practical Utopia’ research agenda

Currently, a number of contributions in mobility studies are looking for fruitful intersections with other ‘adjacent’ approaches . In this spirit, our theoretical paper argues to study one particular aspect: the intersection of social protection and mobilities. Currently, the provision of social services in the ‘West’ is strongly entrenched within nation-state logics, which assume that clients’ immobility is a precondition of service delivery and that national citizenship is the desirable conditionality of gaining social rights. To overcome such a wide-spread conflation of social security with state security, we introduce the heuristic concept ‘social protection’. It allows social security to be imagined beyond a state-centric perspective and avoids the pitfalls of either a citizenship or a migration approach by taking on a mobility perspective. Thus, for scholars anchored in mobility studies we propose how to develop a social security perspective in a progressive way. For readers from other areas, e.g. citizenship, migration or social policy, we will show how a mobility perspective enriched by a No Border approach can overcome a narrow Western, statist and static perspective on social security. Our goal is to conceptually open up what we call a ‘practical utopia’ research agenda, one that expands our political horizons for future and present socialities.     

走向"扁平化"的知识型城市

中国即将成为先进的知识经济大国的趋势,也为其他国家带来了发展机遇,、本文所研究的核心问题是,如果以知识经济发展为指导的管理政策作为工具,一个人口大国的发达与欠发达地区之间的不均衡是否能够以及如何能够“扁平化”。我们特别要关注的是正在发展中的知识社会是否能够缩窄知识鸿沟以及由此缩短整体的发展差距,“扁平化世界”的概念就是大家都在同一水平的起跑线上。我们选择以中国为例,是因为她悠久的历史和地缘政治的复杂性对其他发展中国家具有借鉴意义。不少学者们认为,是邓小平的改革开放政策改变了中国的落后面貌,但笔者却持相反观点,认为中国的兴衰成败,并不单纯地取决于国界的开放与否,而是取决于整个社会是否存在积极的学习态度以及可供借鉴学习的参照体．     

An easy method of constructing latin square designs balanced for the immediate residual and other order effects

Bradley (1958) proposed a very simple procedure for constructing latin square designs to counterbalance the immediate sequential effect for an even number of treatments. When the number of treatments is odd, balance in a single latin square is not possible. In the present note we have developed an analogous method for the construction of such designs which may be used for an even or odd number of treatments. A proof has also been offered to assure the general validity of the procedure.